Wiper or die for use in the coating of wires



March 30, 1948. H. c. HbBAN WIPER OR DIE FOR USE IN THE COATING OF WIRES Filed July 7, 1944 I [riventor Hug/2 Char/e3 Hoban #10144, I M A ltorneys Patented Mar. 30, 1948 VVIPER E DIE'FOR USE IN THE; COATING OF WIRES.

Hugh GharlesHoban, Dartford, England; assignor: to W. T. Henleys Telegraph Works: G'ompany Limited, Dorking, England, a. British company Application Julyi', 1944, Seri'alNo. 543,845 In Great Britain August 4, 1943" 12 Claims.-

In the coating of wires with enamels, lacquers or'other more or less viscous liquid material, itis.

the practice in some cases to use awiper or die through which the coated wire is drawn for the.

purpose of limiting the thickness of the coating by the holding back of surplus material and for the purpose of smoothing the coating onthe wire.

For the performance of these functions the die is provided with a hole of the appropriate shape and dimensions, which depend on the cross-sew tion of the wire and the thickness of coating to be permitted to pass through the die. Inmost cases the coating will be efiected bypassing the wire in succession through the liquid material a number of'times and, after each immersion, passing it through a die so that the thickness of coat ing is gradually built upby a series of passes. In the case of enamels and lacquers the coating may be dried or baked by passing the wire through an oven after leaving the die at each pass. The invention is concerned with the form of the diemember.

In accordance with the invention the opening which forms the die is made in a piece of sheet metal which is partially divided by a cut extending inward from oneside. The disposition is such that the hole forming the die has its boundary divided between the two parts of thepieceof sheet metal and the dividing cut extends from one edge of the piece past the hole towards the other edge, leaving, however, enough metal uncut to give stifiness sufficient to maintain, under normal conditions, the parts of the piece of sheet metal in alignment and proximity as if the piece were undivided, while permitting the two parts to be bent out of their normal positions. By bending these parts in oppositedirections out of the plane of the piece and turning the piece of sheet metal at right angles to its normal position, there is provided a tapering opening leading from one edge of the piece of metal to the die. This gives a very convenient means of threading up a set of dies. If the two parts of the piece of sheet metal forming a die have their free ends bent to be permanently curved oppositely away from the normal plane of the sheet, they serve to guide the wire into the opening between the two pieces. This facilitates the manipulation of the die when placing the wire in it, so that only one hand of the operator is required for the die member. In this manipulation, if the piece of sheet metal is held with its plane substantially parallel with the wire and gripped at the undivided end, the wire, on being brought betweenthe oppositely curved free endsof thetwo parts of the piece, will move these apart and pass between them to the aperture. forming the die. The piece of sheet metal can then beturned back into its normal position, permitting the two parts to spring back into the one plane.v

The invention is illustrated by the accompanyring drawings wherein- Figure 1- i s-a plan: of an example of a die constructed in accordance with the invention,

Figure 2 is an elevation of the die shown. in

Figure 1, and

Figure. 3 is a perspective view of a group of four dies, each: of the form shown in Figures 1 and 2, mounted" side byside in a common frame.

The die" I shown in Figures I and 2, which is suitable for use when'coating fine wire of circular section with a viscous enamel, is formed out of a piece ofsheet' metal, for instance, hard rolled copper or steel, or Phosphor bronze having. available the requisite degree of elastic deformation. The blank is'of rectangular form and about'five times as long as it is wide but it may be longer or'shorter than this. A cut 2 is madawithout removing metal, on the longitudinal centre line from one end to a point about three quarters along the length of the piece. At the end from which the cut is made the two parts 3 and tone one each side of the out, arechamfered ofi to provide a V-shaped opening leading in to the cut. The two charn'fered ends 3a and 4a, are permanently'bent slightly in opposite directions out of the plane of thepiece, as shown in Figure 2. At its-other end the out? leads to an opening t made, for-instance, by slottingor by drilling. This gives more flexibility: at this end of the piece as well as-terminatingthe cut in such a way a-storemove the possibility of extension by tearing. The die aperture is formed by drilling ahole 6 in about the centre of the piece and On the line of the cut 2 The holeismade slightly bell-mouthed on oneside, namely; on that side at which the wire enters thedie.

Figures 1 and= 2show the normal condition of the-die when'it is in use in the machine, the two sides oft-he out being in contact so that'the Wall oft-he hole forming the die aperture is complete. The shape of the die facilitates the pressing apart of the-two sidesof the die by the exertion of very little" force so as to'permit the insertion of the wire lat'erally and avoid any necessity for threading' the hole;

Sheet metal diesconstructed in accordance with this invention. may be mounted side by side in a frame consistingof bars lying above and' below the dies and spaced a short distance apart so as to permit the dies to have a slight play in the direction of travel of the wire, which is taken up as soon as the die engages the viscous cover-- The central part of each lower bar has in its up- 7 7 per surface a recess to receive a number of sheet metal dies, each of the form shown in Figures 1 and 2, the length and depth of the recess being such that each die can float in the direction of travel of the wire and also laterally to a slight extent. By hinging the upper to the lower bars and securing the former by a snap fastening, the frame can be opened readily to permit the dies to be turned so as to lie in a plane normal to the lower bars 8 to facilitate the entry or withdrawal of the wire, a

The improved construction permits the die to be made of very small weight so that the permitted lateral displacement can easily be brought about, thus allowingthe die to follow any wandering of the path of the wire without subjecting the wire to any large lateral force such as would produce local variations in the thickness of the covering.

What I claim as my invention is:

1. "A wiping die for use with the application of enamels, lacquers or the like to wires, comprising a piece of sheet metal partially divided into two parts, each part throughout its length having a width at least several times the thickness of the piece, by a cut. extending inwards from one edge of the piece to and beyond a hole, which forms the die aperture and of which the boundary is divided between the two parts, towards the opposite edge of the piece, leaving enough metal uncut. to give stiffness sufficient under normal working conditions to maintain the parts in alignment and proximity as if the piece were undivided whilst permitting the two parts to be bent out of their normal positions whereby to provide a tapering opening leading from one edge of the piece to the die aperture.

2. A wiping die for use with the application of enamels, lacquers or the like to wires, comprising a piece of sheet metal partially divided into two parts by a cut extending inwards from one edge of the piece to and beyond a hole, which forms the die aperture and of which the boundary is divided between the two parts, towards the opposite edge of the piece, leaving enough metal uncut to give stiffness sufficient under normal working conditons to maintain, as if the piece were undividecL'the parts in alignment and proximity, except at their free ends which arepermanently bent in opposite directions away from the normal plane of the piece whereby to serve t'o'guide the wire to be coated into a tapering opening formed by the temporary deflection of one or both of the two parts from the said plane'and leading from the bent ends to the die aperture.

3. A wiping die for use with the application of enamels, lacquers or the like to wires, comprising a piece of sheet metal partially divided into two parts, each part throughout its length having a width at least several times the thickness of the piece, by a cut extending inwards from the bottom of a V-shaped opening in one edge of the piece to and beyond ahole, which forms the die aperture and of which the boundary is divided between the two parts, towards the opposite edge of the piece, leaving enough metal uncut to give stillness sufi'icient under normal working conditions to maintain the parts inalignment and proximity as if the piece were undivided whilst permitting the two parts to be bent out of their normal positions whereby to provide a tapering opening leading from one edge of the piece to the die aperture.

4. A wiping die for use with the application of enamels, lacquers or the like to wires, comprising a piece of sheet metal partially divided into v two parts, each part throughout its length having a width at least several times the thickness of the piece, by a cut extending inwards from one edge of the piece to and beyond a hole, which forms the die aperture and of which the boundof theirnormalpositions whereby to providea of. the

tapering opening leading from one edge piece to the die aperture. r

5. A wiping die for use with the application of enamels, lacquers or'the like to wires, comprisary is divided between the two parts, towards the 7 ing a substantially oblong piece of sheet metal having in the centre of one of its shorter edges a V-shaped opening the parts on'opposite sides of which are permanently bent in opposite directions out of the plane of the piece to lie at an acute angle to one another and having an Oblong hole in its opposite end and a cut extending from the bottom of the V-shapedopening to and beyond a hole, which forms the die aperture in the central part of the piece, and terminating at that edge of the oblong hole that lies nearestthe die aperture.

6. In combination, a number of sheet' metalwiping dies, each ofthe formspecified'in claim 1, and a supporting frame therefor comprising'a' one end to a lower bar and detachably held at its other end by a snap fastening, the central part of each lower bar having in-its upper surface a recess of which the depth is greater than the thickness of the sheet metal dies and the length is greater than the aggregate width of the dies, whereby to permit'each die to float laterally and in a direction normal to the plane of the die;

7. A wiping die for use with the application of in its other end and a cut extending from the 7 bottom of the first said V-shaped opening to and beyond a second hole which formsthe die aper' ture in the middle part of the strip, andter-- minating at that edge of the first said hole lies nearest the die aperture.

8. A wiping die for use with-the application of enamels, lacquers or the like to wire, comprising a bifurcated thin plate having limbs which lie that in the same plane with their neighborbouring edges, which are notched, in close proximity on each side of the notches, which co-operate to form the die aperture, each of said limbs throughout its length having a width at least several times the thickness of the plate and being easily elastically deflected in opposite directions away from the said plane to form a tapering opening leading to the die aperture but comparatively incapable of relative movement in the said plane.

9. A wiping die for use with the application of enamels, lacquers or the like to wires, comprising a piece of sheet metal partially divided into two parts by a cut extending inwards from one edge of the piece to and beyond a hole, which forms the die aperture and of which the boundary is divided between the two parts, towards the opposite edge of the piece, the said two parts throughout their length each having a width at least several times the thickness of the said sheet metal and being capable of elastic deflection in opposite directions from the normal plane of the piece whereby to provide a tapering opening leading from the first said edge of the piece to the die aperture and being substantially incapable of movement relative to one another within the said plane.

10. A wiping die for use with the application of enamels, lacquers or the like to wire, comprising a piece of sheet metal divided by a cut eX- tending inwards from one edge of the piece to and beyond a hole gfOrming the die aperture towards the opposite edge of the piece, into two limbs united by a body portion whose minimum dimension in the plane of the piece is at least several times as great as the thickness of the piece, whereby the two limbs are substantially incapable of relative elastic movement in the plane of the piece but are readily elastically deflected in opposite directions from the said plane to form a tapering opening leading to the die aperture.

Number 11. A wiping die for use with the application of enamels, lacquers or the like to wire, comprising a piece of sheet metal divided, by a cut extending inwards from the bottom of a 'V-shaped opening in one edge of the piece to and beyond a hole forming the die aperture towards the opposite edge of the piece, into two limbs united by a body portion whose minimum dimension in the plane of the piece is considerably greater than the thickness of the piece, whereby the two limbs are substantially incapable of relative elastic movement in the plane of the piece compared with the ease with which they may be elastically deflected in opposite directions from the said plane to form a tapering opening leading to the di ape-rture.

12. A wiping die for use with the application of enamels, lacquers or the like to wire, comprising a piece of sheet metal divided by a cut extending inwards from one edge of the piece to and beyond a hole forming the die aperture towards the opposite edge of the piece and, terminating at the edge of a second apertur in the piece, into two limbs united by the wall of metal defining said second aperture, said wall having a minimum breadth considerably greater than the thickness of the piece, whereby the two limbs are substantially incapable of relative elastic movement in the plane of the piece compared with the ease with which they may be elastically deflected in opposite directions from the said plane to form a tapering opening leading to the die aperture.

HUGH CHARLES I-IOBAN.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Name Date Miller et a1. Nov. 29, 1870 Sommer Dec. 3, 1929 

